have you tried a different lan socket or a different cable? Have you plugged the laptop in with the cable and tried that. Is it possible for you to borrow another router and see if that works ok? if so the routers sockets have failed. It is a question of trying to establish what the problem actually is. My son in laws laptop will not connect to his router wirelessly but will via cable although his laptop can connect wirelessly with mine. So keep swapping things etc.